This disclosure relates to the hollow molded plastic adapter body which fits between a flexible plastic catheter and the out flow connection of the tube from an administration set. The adapter body is tapered and hollow having a diametrically larger inlet opening at the proximal end than the outlet opening at the distal end. Flexible wings extend from the adapter body for purposes of handling and then securing to the patient. At the distal end this adapter body is provided a fastener connection means such as luer lock threads about the proximal end inlet and a reduced tip for attachment to the end of a flexible catheter tube at the distal end outlet. In use, the adapter body is designed for an over-the-needle insertion procedure. That is to say that, the adapter and its catheter are coaxially carried by a hollow needle during insertion into a human blood vessel. The needle coaxially carries the catheter tightly thereabout and the two are inserted together as a unit with the needle tip penetrating and making an opening followed by the leading (distal) end of the catheter.
In order to facilitate this procedure, the tip of the catheter is chamfered or beveled so that as the needle is placed into the vein; it will easily carry with it the catheter. Similarly, the needle is beveled to facilitate penetration into the blood vessel and the orientation of the bevel relative to the adapter body is important due to the relationship between the wings and the needle. The needle bevel relative to the blood vessel lumen is such that the tip or point of the needle is furtherest from the skin surface during placement, for example, bevel upwardly. Once the catheter is placed within the vessel the needle can be axially extracted and this is done by holding the adapter body by, for example, placing the wings to which the catheter adapter is attached against the patient's flesh and withdrawing the needle by means of the flash back chamber attached at the end of the needle opposite the beveled point or tip.
Adapter bodies have been made with a variety of shapes and configurations such as for example, those shown in U.S. Pat. Nos. 3,348,544, 3,352,306, 3,406,685, 3,515,137, 3,595,230, 3,895,632, and 4,292,970. These shapes and configurations serve to facilitate handling and a variety of other useful purposes. However, none of these or other adapters have been specifically designed to guarantee suture securement of the catheter to the patient and/or the holding of same within the blood vessel.
In particular, the problem of the catheter inadvertently retracting from the blood vessel with blood loss or the loss of the intravenous site is a serious one since it threatens infection and/or bleeding. The additional pain caused to the patient from another catheter placement is also of great concern. As mentioned, catheter adapters have carried means for securement of same to the patient such as for example, wings for adhesive taping to the patient's skin. For suturing such wings have holes at their extremities. While the suturing technique is more secure than taping, wing suturing has problems. The holes in the wings are located laterally spaced away from the adapter body and when the wings are flexible, the displaced location of the holes can allow axial displacement of the adapter body. That is to say that, when the wings are made fragile and flexible in order to adapt to the contour of the patient's body. Suturing tied through the tips of the wings in the premade holes tends to aggravate a stress condition and give a loose attachment. The suture thread is very thin as is the cross section of the flexible wing, thus resulting in a potential for tearing either of the skin of the patient or the cross section of the wing.